In den Beiträgen dieser Rubrik geht es um Methoden, mit denen sich feststellen lässt inwiefern eine gewünschte Eigenschaft erfüllt ist.
Free Sintering of PTFE-PEEK Blend in Air Atmosphere and its Tribological and Mechanical Properties
Free sintering in air atmosphere of an innovative bearing material based on poly(tetrafluoroethylene) (PTFE) and 15 wt. % poly(etheretherketone) (PEEK) was investigated from the point of view of degradation and the final tribological and mechanical properties. The differential scanning calorimetry (DSC) measurement program for determining the degree of degradation was newly optimized. A sintering program that caused almost no degradation of PEEK in the air atmosphere was found and used for test sample preparation. The tribological properties were measured by the Ball-on-Disc method and compared to those of the pure PTFE and highly degraded PTFE-PEEK blend. In addition, the basic mechanical properties and scratch hardness were measured. Finally, the fracture areas were studied by digital microscopy.Weiterlesen...
New Thermoset Capillary Rheometer (TCR) to evaluate Flow and Thermal Behavior of Thermosets
To evaluate flow and thermal properties of thermosetting materials at pressures comparable to processing operations, a new Thermoset Capillary Rheometer (TCR) is introduced. Material viscosity is measured before curing and during curing. This is used to determine the curing curve and gel time. Depending on the mold temperature, some compounds show decrease in pressure due to shrinkage whereas some other materials show increase in pressure due to degradation. As the pressure increases, shrinkage and degradation decrease. Thermal behavior of the compound during curing is monitored with gradient temperature sensors. The time at which the maximum exothermic peak happens correlates with curing speed.Weiterlesen...
Normen und Spezifikationen bei der Elastomerprüfung
Wann ist es eine Norm oder eine Spezifikation? Und wie unterscheiden sich Werk- und DIN-Norm? Ein Prüflabor entwirrt nachfolgend den Knoten.Weiterlesen...
Deshalb ist es sinnvoll, einfache Modelle auf experimentelle Befunde anzuwenden
An Technischen Hochschulen wird die theoretische Ausbildung durch Praktika begleitet. Die Versuchsaufbauten ermöglichen die Zusammenhänge zu erkennen und verdeutlichen, dass mit einfachen Prüfmaschinen zielführende Ergebnisse erzielt werden können.Weiterlesen...
Similarities in Stress-Strain-Curve and electrical Conductivity
Electroconductive composites were prepared using either styrene–butadiene rubber or polycaprolactone matrix with varying amounts of two grades of electroconductive carbon black. Electrical conductivity was measured during deformation and at the same time a stress-strain-curve was recorded. The dependences of electrical conductivity on deformation exhibit several extremes. All conductivity changes were interpreted in terms of either the conductive pathways destruction or the formation of new ones, Thus, electrical conductivity can be correlated with the specific features of the physical network of the reinforcing filler that affect the mechanical properties of the composite.Weiterlesen...
Rohling bei Vulkanisation identifizieren
Der UHF-Lese-/Schreibkopf F190-B40 von Pepperl+Fuchs ermöglicht das eindeutige Identifizieren von Reifenrohlingen während der Vulkanisierung.Weiterlesen...
Wie sich die Eigenschaften von Talkum durch Oberflächenmodifikation ändern
Basierend auf einer feinen Talkumtype, wurde die neue Füllstoffproduktgruppe namens Struktosil entwickelt. Die Füllstoffe erhalten durch eine nachträgliche Oberflächenmodifizierung diverser Funktionalitäten, durch die die Performance im Endprodukt verbessert werden kann.Weiterlesen...
Dynamic mechanical Properties of radiation-modified Peroxide cured PVMQ elastomers at their natural frequency
The effects of co-agent (TAIC) and ionizing radiation on the dynamic mechanical properties of phenyl-vinyl-methyl-polysiloxane (PVMQ), cured thermally with perox-ide, tested on Dynamic Mechanical Yerzley Oscillograph (DMYO V) under dynamic compression and static hysteresis. The vibration plots, tan delta, absorbed energy at loading, returned energy at unloading, damping coefficient, point modulus, elastic modulus, resilience and cross-link density parameters were reported. The results indicate that co-agent presence and gamma irradiation are two important parameters for controlling vibration damping properties at the natural frequency of silicone elastomers.Weiterlesen...
Nachhaltige Produktion mit vollautomatischer Farbkorrektur bei der Compoundierung
Die Farbe eines Endproduktes ist heute ein wichtiger Aspekt moderner Brandings. Mit dem Farbsystem Color Adjust von Krauss Maffei, Hannover, gehören Farbschwankungen bei farblich unterschiedlicher Inputware nun der Vergangenheit an.Weiterlesen...
Certification of stitched Composite Aircraft Structures based on multiscale Damage Analysis
The certification of stitched composites for aircraft structure is still problematic due to the lack of dependable unknown manufacturing factors that can considerably influence their performance. In this research, the mechanical properties of specific stitching configuration using multiscale modeling are discussed.Weiterlesen...